1. Exhibit 1 NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. MA-PD is Medicare Advantage Prescription Drug Plan. Analysis includes non-LIS Medicare Part D enrollees in a PDP or MA-PD in one or more annual enrollment period from 2006 to 2010; estimates are averaged across four annual enrollment periods, 2006-2010. See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. Most Non-LIS Medicare Part D Enrollees Did Not Switch Plans Voluntarily During an Open Enrollment Period, 2006-2010

2. Exhibit 2 NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. MA-PD is Medicare Advantage Prescription Drug Plan. See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. Switching Rates Among Non-LIS Part D Enrollees Were Similar Across Four Annual Enrollment Periods and Different Plan Types 2006-20072007-20082008-20092009-2010

3. Exhibit 3 NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. Analysis includes non-LIS Medicare Part D enrollees in a PDP continuously from 2006 to 2010 (n=313,418). See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. Among Non-LIS Part D Enrollees Continuously Enrolled in PDPs From 2006 to 2010, 7 out of 10 Never Voluntarily Switched Plans

4. Exhibit 4 NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. Analysis includes non-LIS Medicare Part D enrollees in a PDP continuously from 2006 to 2010 (n=313,418). See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. Share of enrollees: 100%77.1%16.7%5.1%1.1% Switching Rates In 2009-2010 Were Higher Among Non-LIS PDP Enrollees Who Previously Switched Plans and Increased With the Number of Prior Switches Number of Switches Prior to the 2009-2010 Enrollment Period

5. Exhibit 5 NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. Analysis includes non-LIS Medicare Part D enrollees in a PDP in one or more annual enrollment period from 2006 to 2010; excludes those who switched to a Medicare Advantage drug plan; estimates are averaged across four annual enrollment periods, 2006-2010. See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. A Larger Share of Non-LIS PDP Enrollees Who Switched Plans Had Lower Costs in Year 2 Than in Year 1, Compared to Non-Switchers, 2006-2010 Premiums Out-of-pocket drug costs

6. Exhibit 6 NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. Analysis includes non-LIS Medicare Part D enrollees in a PDP in one or more annual enrollment period from 2006 to 2010; excludes those who switched to a Medicare Advantage drug plan; estimates are averaged across four annual enrollment periods, 2006-2010. See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. Switching Rates Were Higher Among Non-LIS PDP Enrollees Facing Larger Premium Increases, Compared to Other Enrollees, 2006-2010 Change in Monthly PDP Premium From Year 1 to Year 2 Share of enrollees 100%13.0%66.6%16.6%3.8%

7. Exhibit 7 Share of enrollees 100%3.6%83.5%12.7% NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. Analysis includes non-LIS Medicare Part D enrollees in a PDP in the 2009-2010 annual enrollment period (n=438,006); excludes those who switched to a Medicare Advantage drug plan. See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. Switching Rates Were Higher Among Non-LIS PDP Enrollees Facing a Higher Deductible, Compared to Other PDP Enrollees, 2009-2010 Change in PDP Deductible From Year 1 to Year 2

8. Exhibit 8 NOTES: LIS is Low-Income Subsidy. PDP is prescription drug plan. Analysis includes non-LIS Medicare Part D enrollees in a PDP in one or more annual enrollment period from 2006 to 2008; excludes those in PDPs adding gap coverage and those who switched to a Medicare Advantage drug plan. See Appendix 1 for full methodology. SOURCE: Georgetown/NORC/Kaiser Family Foundation analysis of Medicare Beneficiary Summary Files and Plan Characteristics Files, 2006-2010. Switching Rates Were Higher Among Non-LIS PDP Enrollees Who Lost Brand-Name Gap Coverage, Compared to Other Enrollees, 2006-2008 Share of enrollees 100%5.0%89.0%100%1.3% 97.8% 2006-20072007-2008